Automatic firearm



A. FURRER AUTOMATIC FIREARM Patented Een. 9, 1924.

ADOLF FURRER; F BERNE, SWITZERLAND, ASSIGNOR TO SCHWEIZERISCHE INDUS- TRIE GESELLSCHAFT, 0F NEUHAUSEN, SCHAFFHAUSECN, SWITZERLAND.

AUTOMATIC FIREARM.

certain new and useful Improvements in Automatic Firearms, of which the following is a .speciicatiorh The present invention has reference to automatic rearms or machlne guns and has for its purpose to provide a weapon of very greatly simplified construction, in which the number' of working parts is very small, the gun being thoroughly efiicient in operation, capable of great rapidity of tiring and being of very light weight.

With these objects in view the present invention provides in an automatic tire arm an articulated breech mechanism actuated by the recoil, which mechanism comprises a breech bolt frame movable in stationary guides of the stock and a breech bolt proper movable in this breech bolt frame which bolt closes the rear end of the barrel. The new weapon comprises a pivoted link, moving the breech bolt in t-he movable breech bolt frame which link is not only rotatably mounted in the said movable breech bolt frame Vbut is pivotally connected at its rear end t0 a-supporting link which rotates on a pin in the stock of the weapon. During the recoil movement of the breech bolt frame in its stationary guides a movement ofthe supporting link takes place whereby the pivoted link is also moved and in turn produces the movement of the breech bolt in the breech bolt frame which is itself moving, and effects the opening of the rear end of the barrel. The distance through which 'the breech .bolt moves in the breech bolt frame, the period at which the relative movement of the breech bolt in relation to the breech bolt frame begins and again ends, can be determined by the correctdimensioning of the parts. A further feature resides r therein that of the members serving to move A `the breech bolt in the breech bolt frame some l invention consists in the novel parts more fully hereinafter disclosed and particularly Application inea April 14, 1924. serial No. 706,504.

pointed out in the claims.

of this specificationV in which like numerals designate like parts in all the views:

Fi l is a longitudinal section with the breec mechanism in the closed position,

Fig. 2 is a longitudinal section with the breech open,

Referring to thel accompanying drawings forming a part Fig. 3 is a longitudinal section in a plane.

at right angles tothe sections shown in Figs. 1 land 2. The link vmembers are shown in elevation. l

Fig. 4 shows by means of two curves the dependency of the recoil movement of the breech bolt on that of the breech bolt frame. The abscissae are the paths of the breech frame, the ordinates the corresponding. paths of the breech bolt. Curve I indicates the path of the breech bolt lrelatively to the stationary 'parts of the wea on and curve II the path of the breech bo t relatively to the breech-bolt frame. Whilst in Figs. l, 2 and 3 the trigger and sear mechanism has been omitted for the sake of clearness.

breech bolt has been released and moves 'forwards for firing. Fi v7 shows the position of the parts, by close breech when the trigger movement is reducedl by turning a control lever so that the striker can only be released, even in repeat firing, when the movable parts of the breech ymechanism are wholly in the forward position. The position of the parts shown yin Fig. 7 corresponds with the moment 'of firing; the movable parts have passed wholly into thefro'nt position, the striker has been released and slides forwards'for tiring.

The barrel 1 is rigidly connected with-the casing or breech bolt frame 2 and during ring slides backwards under the action of the recoil in guides of the stationary part 3 inthe direction of the barrel axis. In this manner the spring 4 is tensioned, this spring returning the movable parts of the breech mechanism after the completion lof the recoil into the firing position. In the breech bolt frame 2 there is mounted the breech bolt or breech block 5 which is also movable in guides in the direction of the barrel axis'. This breech bolt is connected by an intermediate link 6 with the front end of the pivoted link member 7. The latter is rotatably mounted Ain the breech bolt frame 2. on a pivot 8. The rear end of the link member 7 is connected by means of the pivot pin V9 with one end of the supporting link 10, of which the otherend 1s rotatably mounted on the pivot 11 in the stock of the Gun.

c To relieve the link pivots from the action of the recoil force during firing the intermediate link G is provided with a projection .12, which, when the breech is closed, presses As shown by curve .II inFig. e the breech l bolt only starts to move away from the rear end of the barrel after the barrel and the breech bolt frame have passed through a certain distance which in magnitude defpends upon the dimensions of the links, particularl the supporting link 10. The speed of the reech bolt relatively to the breech bolt frame is zero at the beginning of the return movement, it then gradually increases and is again reduced towards the end of. the return movement. The breech at the beginn ning of the return movement thus remains closed for a time and it is again closed before the movement has been completed. Consequently it is possible in the case of automatic repeat firing to deliver the shotI before the return movement has been lcornpleted for the purpose of reducing the recoil. Figs. 5, and 7 illustrate how the shot delivery can be` controlled. A

The firing pin or striker 16 is provided with aprojectlon 17 and is movably mounted inthe breech bolt v5. The sear 19 is rotatable in the breech bolt frame and its end 18 1s pressed by a springtowards thev firing pin 16. During the forward movement of the breech bolt 5 the projection 17 catches on the end 18 whereby the striker spring tensioned. By means of the trigger 20, the

trigger rod 22, which is under t' 1e action of the spring 21, is pulled back until the trigger 20 comes against the short cam of the controlling `lever .23. The projection 24 at and the Vitirin 'that in repeat lirin the front end of the trigger rod 22 thereby slides on Athe inclined surface at the front end of the sear 19 and when the trigger rod 22 is pulled fully back presses the end 18 of the scar 19 outwards to such an extent that the projection 17 of the striker is released wards under t e action of the striker spring. The movement of the trigger and thus of the rod 22 can be-so adjusted that when the trigger bears fully against the control lever the striker is released at the second and fo owing shots before the movable parts of the breech mechanism have returned fully into the forward position. The release of the first shctin repeat firing and all the shots in single iring is eifected Vin the forward or closed position of the breech mechanism before the triggerl 20 pin can move rapidly for-Y comes to bear against the short cam on the controlling lever 23. The control of the delivery or the shots in repeat liring can be disengaged by moving the control lever 23 into t e position illustrated in Fig. 7. The longer cam of the control lever,l then prevents a-further backward mpvement of the trigger rod 22 and the .release of the shots can only be effected after the movable sys tem has moved fully forwards.

. What I wish to secure by Letters Pat` l ent 1. Automatic fire arm with articulated breech mechanism actuated bythe recoil,

'which mechanism comp ises a breech bolt and a breech frame movable in stationary guides the breech bolt being movable in the breech frame characterized by the fact that apivoted lin moving the breech bolt and rotatably mounted on a pivot in the breech frame is at its rear end ivoted to one end of a supporting link w ich rotates on a shaft in the stationary part of the weapon.

2. Automatic lire arm with link bolt according to claim 1, characterized by the fact that the intermediate link connecting the breech bolt to the pivoted link is provided with a projection which when the breech bolt isfclosed `enga es between the breech bolt and the ivote, link.

3. Automatic fire arm with link bolt aci@ cording to claim 1, characterized by the fact that the pivoted link is provided with bosses arranged concentrically to the pivot which., when the breech is closed, engage with corresponding recesses in the breech frame.

4f.. Automatic, re arm with'li'nk bolt according to claim 1, characterized by the fact that the delivery of shots in automatic. re-

peat liring can be controlled b drawing `the y AnoLF FUR ER. 

